Neuromodulators do not appear effective for post-viral parosmia.

The COVID-19 pandemic brought attention to post-viral smell distortion, or parosmia, which is defined as a qualitative dysfunction resulting from distorted odor perception in the presence of an odorous medium. Very often, qualitative and quantitative alterations occur simultaneously. Patients severely affected by qualitative odor disorders find that their quality of life has deteriorated. For quantitative loss from viruses, the role of olfactory training has been emphasized, along with high volume steroid nasal irrigations, and even injections with platelet-rich plasma. However, there has been no high-level evidence demonstrating an effective treatment for qualitative olfactory disorders.